It is often that the windscreen wiper cannot effectively clean the glass of a car. This is because the rubber strip on the windscreen wiper deforms due to the sunlight and rain.
To improve-above mentioned problem, the windscreen wiper supporting device is developed. One of such prior art is illustrated in FIG. 1. The supporting device includes a body 3, a spring 30, an supporting unit 31, etc. When the windscreen wiper 1 is not used. The ejection unit 31 moves to the lower side of the windscreen wiper 1. By the pressing force of the windscreen wiper 1 and the friction force between the cover 33 and the glass 2, the body 3 and the supporting unit 31 will support the windscreen wiper 1 so that it will not eject out. Thus the windscreen wiper 1 separates from the glass 2 so as to protect the windscreen wiper 1 from destroy. On the contrary, when it is desired to use the windscreen wiper 1, the body 3 and the supporting unit 31 will sense the operation force from the windscreen wiper 1, the spring 30 will eject the supporting unit toward a front end of the windscreen wiper 1 so that the supporting unit 31 do not contact the glass 2 and thus the glass 2 will not be scratched.
Above mentioned structure has the following three disadvantages.
As illustrated in FIG. 1, the spring 30 is in tension for a long time, the spring 30 will fatigue and thus the supporting unit 31 can not return to the original position. Thus the glass 2 will be hurt.
Furthermore, the element of the supporting device exposes out. In frigid zone or winter, the device can not work due to the elements freezes, and thus the supporting unit 31 can not work normally and the glass is scratched. However, this will induce accident in driving.
Moreover, see FIG. 1, the prior art windscreen wiper exposes out and thus is easy to rust. For a long time, the element of windscreen wiper will be destroyed and the lifetime thereof is shortened.